一个正规的网站，在需要上传图片时，往往都会需要在图片上增加自己网站的LOGO水印。那么如何实现这一步骤呢？首先让我们来了解PHP图片加水印的原理。
通过判断文件类型建立图形，然后把其复制到原建立的图形上，填充并建立rectangle，以备写入imagestring()或是在原已经定好的图像程序当中判断水印类型：一是字符串，另是增加一个图形对象在上面。以下是PHP图片加水印的转载！
参数说明:
$max_file_size : 上传文件大小限制, 单位BYTE
$destination_folder : 上传文件路径
$watermark : 是否附加水印(1为加水印,其他为不加水印);
PHP图片加水印使用说明:
1. 将PHP.INI文件里面的”extension=php_gd2.dll”一行前面的;号去掉,因为我们要用到GD库;
2. 将extension_dir =改为你的php_gd2.dll所在目录;
3. http://www.gaodaima.com/list/list_15_1.htm
PHP图片加水印的代码示例：
<BR>//上传文件类型列表 <BR>$uptypes=array( <BR>'image/jpg', <BR>'image/jpeg', <BR>'image/png', <BR>'image/pjpeg', <BR>'image/gif', <BR>'image/bmp', <BR>'image/x-png' <BR>); <BR>$max_file_size=2000000; //上传文件大小限制, 单位BYTE <BR>$destination_folder="uploadimg/"; //上传文件路径 <BR>$watermark=1; //是否附加水印(1为加水印,其他为不加水印); <BR>$watertype=1; //水印类型(1为文字,2为图片) <BR>$waterposition=1; //水印位置(1为左下角,2为右下角 <BR>,3为左上角,4为右上角,5为居中); <BR>$waterstring=" <BR>http://www.xplore.cn/"; //水印字符串 <BR>$waterimg="xplore.gif"; //水印图片 <BR>$imgpreview=1; //是否生成预览图(1为生成,其他为不生成); <BR>$imgpreviewsize=1/2; //缩略图比例 <BR>?> <BR> <BR> <BR><title>ZwelL图片上传程序</title> <BR><style type="text/css"> <BR><!---ecms -ecms -ecms <BR>body <BR>{ <BR>font-size: 9pt; <BR>} <BR>input <BR>{ <BR>background-color: #66CCFF; <BR>border: 1px inset #CCCCCC; <BR>} <BR>--> <BR></style> <BR> <BR><body> <BR><form enctype="multipart/form-data" <BR>method="post" name="upform"> <BR>上传文件: <BR> <BR><br> <BR>允许上传的文件类型为:<?=implode(', ',$uptypes)?> <BR> <BR><?php <BR>if ($_SERVER['REQUEST_METHOD'] == 'POST') <BR>{ <BR>if (!is_uploaded_file($_FILES["upfile"] <BR>[tmp_name])) <BR>//是否存在文件 <BR>{ <BR>echo "图片不存在!"; <BR>exit; <BR>} <BR>$file = $_FILES["upfile"]; <BR>if($max_file_size <$file["size"]) <BR>//检查文件大小 <BR>{ <BR>echo "文件太大!"; <BR>exit; <BR>} <BR>if(!in_array($file["type"], $uptypes)) <BR>//检查文件类型 <BR>{ <BR>echo "文件类型不符!".$file["type"]; <BR>exit; <BR>} <BR>if(!file_exists($destination_folder)) <BR>{ <BR>mkdir($destination_folder); <BR>} <BR>$filename=$file["tmp_name"]; <BR>$image_size = getimagesize($filename); <BR>$pinfo=pathinfo($file["name"]); <BR>$ftype=$pinfo['extension']; <BR>$destination = $destination_folder. <BR>time().".".$ftype; <BR>if (file_exists($destination) && <BR>$overwrite != true) <BR>{ <BR>echo "同名文件已经存在了"; <BR>exit; <BR>} <BR>if(!move_uploaded_file ($filename, <BR>$destination)) <BR>{ <BR>echo "移动文件出错"; <BR>exit; <BR>} <BR>$pinfo=pathinfo($destination); <BR>$fname=$pinfo[basename]; <BR>echo " <font color="red">已经成功上传 <BR></font><br>文件名: <BR><font color="blue">".$destination_folder. <BR>$fname."</font><br>"; <BR>echo " 宽度:".$image_size[0]; <BR>echo " 长度:".$image_size[1]; <BR>echo "<br> 大小:".$file["size"]." bytes"; <BR>if($watermark==1) <BR>{ <BR>$iinfo=getimagesize($destination,$iinfo); <BR>$nimage=imagecreatetruecolor($image_size[0] <BR>,$image_size[1]); <BR>$white=imagecolorallocate($nimage,255,255,255); <BR>$black=imagecolorallocate($nimage,0,0,0); <BR>$red=imagecolorallocate($nimage,255,0,0); <BR>imagefill($nimage,0,0,$white); <BR>switch ($iinfo[2]) <BR>{ <BR>case 1: <BR>$simage =imagecreatefromgif($destination); <BR>break; <BR>case 2: <BR>$simage =imagecreatefromjpeg($destination); <BR>break; <BR>case 3: <BR>$simage =imagecreatefrompng($destination); <BR>break; <BR>case 6: <BR>$simage =imagecreatefromwbmp($destination); <BR>break; <BR>default: <BR>die("不支持的文件类型"); <BR>exit; <BR>} <BR>imagecopy($nimage,$simage,0,0,0,0, <BR>$image_size[0],$image_size[1]); <BR>imagefilledrectangle($nimage,1, <BR>$image_size[1]-15,80,$image_size[1],$white); <BR>switch($watertype) <BR>{ <BR>case 1: //加水印字符串 <BR>imagestring($nimage,2,3,$image_size[1]-15, <BR>$waterstring,$black); <BR>break; <BR>case 2: //加水印图片 <BR>$simage1 =imagecreatefromgif("xplore.gif"); <BR>imagec<strong>+本文来源gao@daima#com搞(%代@#码网</strong><pre>搞代gaodaima码
opy($nimage,$simage1,0,0,0,0,85,15);
imagedestroy($simage1);
break;
}
switch ($iinfo[2])
{
case 1:
//imagegif($nimage, $destination);
imagejpeg($nimage, $destination);
break;
case 2:
imagejpeg($nimage, $destination);
break;
case 3:
imagepng($nimage, $destination);
break;
case 6:
imagewbmp($nimage, $destination);
//imagejpeg($nimage, $destination);
break;
}
//覆盖原上传文件
imagedestroy($nimage);
imagedestroy($simage);
}
if($imgpreview==1)
{
echo “
图片预览:
“;
echo “<ccid_file values="\" width=".
($image_size[0]*$imgpreviewsize).”
height=”.($image_size[1]*$imgpreviewsize);”
echo ” alt=\”图片预览:\r文件名:”.
$destination.”\r上传时间:\” />”;
}
}
?>
大家也可以参考 图片加水印的PHP类
转载请注明原文链接：php 图片加水印与上传图片加水印php类_php技巧
